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  <title>Document</title>
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<body>
  <script>
    let arr = [15, 19, 21, 33, 18, 24]
    // 设置两个值  一个为和 一个为平均数
    let sum = 0
    let pingjun = 0
    for (let i = 0; i < arr.length; i++) {
      // 先算和再算除
      sum += arr[i]
      pingjun = sum / 6

    }
    console.log(pingjun);
  </script>
</body>

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